Valve



1938- w. E. SWARTZWELDER VALVE Filed Jan. 12, 1937 2 sheets-sheet 1 fliE fi warizwelder ATTORNEY Patented Nov. 29, 1938 UNITED STATES PATENT OFFICE VALVE -Willlam E. Swar'tzwelder, Cumberland, Md.

Application January 12, 1937, Serial No. 120,295

Claims. (or. 188-152) This invention relates to valves 'for vacuum operated brakes of motor vehicles and has for the primary object the provision of a simple and inexpensive device of this character which may be 6 readily substituted. for the control valve now in,

With these and other objects in view, this invention consists in certain novel features of con-e struction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description 25 and accompanying drawings, in which Figure 1 is a fragmentary diagrammatical view showing a vacuum operated brake system with a control valve adapted thereto and constructed in accordance with my invention.

Figure 2 is a vertical sectional view illustrating the valve with the valve elements thereof occupying positions when the brakes are in neutral or non-braking position.

Figure 3 is a view similar to Figure 2 showing 5 the position occupied by the valve, elements during the initial or part movement of the brake pedal towards brake applying position.

Figure 4 is a view similar to Figures 2 and 3 showing the valve elements occupying their posi- 40 tions when the brake pedal has completed its initial position and the brakes partly applied.

- Figure 5 is a view similar to Figures2, 3 and showing the position of the valve elements when Referring in detail to the drawings, the numer- 65 al i indicates a part of a brake rigging of a motor vehicle including a pivotally mounted lever 2 to which is connected the piston 3 of a vacuum operated brake booster 4, consisting of a cylinder 5 in 1 which the piston 3 is located and has connected 60 to opposite endsthereof pipes i .and l.

The numeral 8 indicates a brake pedal connected by. a pin and slot connection to a rod 9.

The rod 9 forms a part of the present invention.

A housing ill of sectional formation has a bore i i to 'slidably receive the rod 9. Located in the housing is a diaphragm i2 forming therein vacuum chambers l3 and i4. The diaphragm has an opening, the walls of which have a comparatively tight fit with the rod 9. However, the rod 9 is free to slide without affecting the position of the diaphragm. .A spring seat i5 is secured to the rod 9 and is located in the vacuum chamber i3. A coil spring i6 surrounds the rod 9 with one end engaging the seat i5 and the other end engaging the diaphragm and which provides a yieldable drive between the rod 9 and the diaphragm.

An externalthreaded boss i1 is formed on the housing I exteriorly thereof and'receives the rod 9. A coupler i8 is threaded on the boss i1 and forms a part of a rod i9 which has a pin and slot connection with one end of the brake lever 2. A spring seat 20 is secured to the rod 9 within the coupler l8 and one end of acoil spring 2i bears thereagainst and the other end of the spring seats against the housing in within the boss ii. The spring 2i compresses by the rod 9 moving with the brake pedal towards brake applying position and offers suiiicient resistance to the movement of the brake pedal 8 by the foot of the operator to assure smooth operation or movement of the brake pedal under foot pressure. The brake pedal 8, as shown in full line in Figure 1 is the non-application of the brakes and the spring [6 issubstantially relaxed. 1

The housing III has formed therein passages 22 and 23 both of which communicate with the position occupied by saidfoot pedal during the the stems of which slide in guides 28 formed in the housing iil. A com'paratively light coilspring 29 acts 'on the valve element 26to engage the latter with the seat 2,. I

-A bracket 30 is secured to the diaphragm i2 and pivotally supports a lever 3i. The lever is pivoted, intermediate its ends to the bracket 30 and one end of said lever has apin and slot connection with the valve element 26 and the other end of the lever has "a pin and slot connection with the valve element 21. One end of the passage 22 opens to the atmosphere. A pipe 32 has branches A, B and C and the branch A isconnected to the passage 23, while the branch 13 is connected to the-vacuum chamber i3 and has located therein a valve 34 of the twoway type,

that is, the valve may be positioned to close the branch B to the vacuum chamber i3 and at the same time vent the chamber l3 to the atmosphere or may bepositioned to communicate the branch B with the vacuum chamber l3. A flexible pipe connects the pipe 32 to an intake manifold 36 of the engine of the motor vehicle so that a constant vacuum is maintained in the pipe 32 while the engine is operating. While I have described and shown the pipe 32 as being connected to the intake manifold of an engine forthe purpose of establishinga vacuum in the pipe 32 the latter may be connected to some other vacuum source. The branch C of the pipe 32 is connected to the pipe 6 by a flexible pipe 31. Connected with the vacuum chamber I4 is a pipe 38 and the latter is connected to the pipe 1 by a flexible pipe 39. During normal operation of the brakes by my invention, the valve 34 is positioned to communicate the branch 3 with the vacuum chamber l3 so that aslong as there is a vacuum in the pipe 32 a vacuum will be had inbranch -B to the vacuum chamber l3 and open the latter to the atmosphere.

The piston 3 moves to the left in Figure 1 to apply the brakes and to the right to release the brakes and occupies a position at the right end of the cylinder when the brakes-are non-applied. During the non-application of the brakes the pedal. -8 occupies a full line position in Figure 1, the diaphragm as shown in Figure 2 with the valve element 21 unseated and the valve element 26 seated. The valve elements thus positionedjpermits vacuum to be developed in the chambers l3 and I4 and the Vacuum remains constant in the chamber i3 either during the application or non-application of the brakes by said chamber i3 being in direct communication with the branch B of the pipe {32. The initial movement of the brake pedal 8 towardsbrake applying position causes a sliding movement of the rod 9 tensioning the spring 16 and the latter places pressure on the diaphragm I 2 flexing the latter and thereby causing the valve 26 to become unseated and the' valve 21 to become seated, as shown in Fig. 3. The valve 26 becoming unseated opens the vacuum chamber l4 to the .atmosphere for a limited time and as soon as the brake pedal 8-stops its movement towards brake applying position, the valve 26 seats due to increase of atmospheric. pressure in chamber l4,

closing thevacuum chamber I4 to the atmos-' phere. Thus, the vacuum in thevacuum chamber M has been reduced to some extent. The reducing of the vacuum in the chamber i4 reduces p the vacuum at one side of the piston 3 permitting the same to move a limited distance to the left in Figure l and thereby bring about a partial application of the brakes. This partial. applicavacuum chamber l4 and the vacuum at one side of the piston 3, thus bringing about further application of the brakes. During the application of the brakesthe valve 21 remains-closed andis aided in maintaining itsseated positionbythe *vacuum in the passage 23 from the lira'nch A.

On a full or complete depression of the. brake pedal 8 to bring about full or complete brake I action, the valve element 26 opens and remains open, as shown in Figure '5, depleting the vacuum in the vacuum chamber l4, consequently permitting'the piston 3 to move to its fullest extent in the direction of the left in Figure 1. 'When the brakes have been fully applied, the spring I6 is substantially fully compressed, as shown in Figure 5. Should the vacuum mechanism fail from some cause, the brakes can be applied mechanically by fully depressing the brake pedal Bcausingthe rod 9 to slide relative to the housing I until the spring seat 28 abuts the boss I! which brings about -a movement of the housing with the rod 9 and the housing being connected to the brake lever 2 rocks'the same on its pivot and applies the brake mechanism. When the brakes are applied through my invention and the valves occupy the position as shown in Figure 5 with the spring l6 substantially compressed and it is desired to release the brakes, the brake pedal 8 is allowed to move towards non-brake applying position releasing the pressure on the spring l6 and the latter bearing against the diaphragm and the seat i5 of the rod 9 repositions the diaphragm, as shown in Figure 2, which unseats the valve 21,and'seats the valve 26 so that vacuum is again restored in the vacuum chamber l'4. As soon as the vacuum isequal in'the chamber I3 and M, the piston 3 may return to neutral or normal position by the brakes releasing. It is to be understood that the brakes'always release by spring action when the fluid pressure em- Also, this atmospheric pressure influences the diaphragm l2 to flex the same in an opposite direction aided by the vacuum in the chamber l3, bringing about a further compressing of the spring l6 also permitting the spring 29 to seat the valve element 26 cutting off the chamber i l to the atmosphere. Itwill, therefore, be seen that the brakes are partially applied and that the diaphragm I2 is substantially restored to normal position so that when the brake rod 9 is moved again by further movement of the brake pedal 8 towards brake applying position the dia- ;phragm will be again flexed to unseat the valve element 26 and further lower the vacuum in the chamber l4 and bring about complete application oi' the brakes. This state of operation and the position of the valve elements is clearly shown in Figure 5 The diaphragm is held flexed by "the position of the rod 9 due to the brake pedal 8 being in full brake applying position.

Should it be desired to manually release the foot pedal 8 and still maintain the brakes applied, the valve.

34 is operated to close the branch B to the chamber I3 andsimult'aneously vent the chamber l3 consequently remain as shown in Figure 4 with the atmospheric pressure acting on the piston 3 l to retain the brakes applied.., The use of the vvalve 34, is employed only when the driver of the vehicle desires to leave the vehicle with the brakes applied.

What is claimed is:

1. In combination with brakes of a motor vehicle including a brake rigging and a vacuum booster cylinder having a piston connected to the rigging and a vacuum source and a brake pedal for applying the brakes, a rod connected to said pedal, a housing slidably receiving said rod, means connecting said housing to the brake rigging, a diaphragm in said housing and forming vacuum chambers therein, means connecting the diaphragm to said rod, means connecting one of the chambers to the vacuum source for maintaining a constant vacuum therein, means connecting the other vacuum chamber to the booster cylinder at one side of the piston, means connecting the vacuum source to the booster cylinder at the other side of the piston, means connecting the last named vacuum chamber to the vacuum source and including a valve mechanism,

a valve mechanism for opening and closing the last-named vacuum chamber to the atmosphere, and means connecting the valve mechanisms to the'diaphragm,

2. In combination with brakes of a motor vehicleincluding a brake rigging and a vacuum booster cylinder ,having a piston connected to the rigging and a vacuum source and a brake pedal for applying the brakes, a rod connected to said pedal, a housing slidably receiving said rod,

' means connecting said housing to the brake rigging, a diaphragm in said housing and forming vacuum chambers therein, means connectingthe diaphragm to-said rod, means connecting one of the chambers to the vacuum source for maintaining a constant vacuum therein, means con-' necting the other vacuum chamber to the boost er cylinder at one side of the piston, means connecting the vacuum source to th'e'booster cylinder at the other side of the piston, means connecting the last named vacuum chamber to, the

vacuum source and including a valve mechanism, a valve mechanism for opening and closing theing vacuum chambers therein, means connecting the diaphragm to said rod, means connecting one of the chambers. to the vacuum source for maintaining a constant vacuum therein, means connecting the other vacuum chamber to the booster cylinder at one side of the piston, means connecting the vacuum source to the booster cylinder at he other side of .the piston, means connectin the last named vacuum chamber to'thevacuum source and including a valve mechanism, a valve mechanism for opening'and closing the last named vacuum chamber to the atmosphere, and a lever connecting the valve mechanisms and pivoted on the diaphragm.

4. In combination with brakes oi a-motor vehicle including a brake rigging and a. vacuum booster cylinder having a piston connected to the rigging and a vacuum source and a brake pedal for applying the brakes, a rod connected to said pedal, a housing slidably receiving the rod, means connecting said housing to the brake rigging, a diaphragm in said housing and forming vacuum chambers therein and slidable on said rod, means including a manually actuated control and vent valve connected to one of said chambers and to the vacuum source, means connecting the other vacuum chamber to the booster cylinder atone side of the piston, means connecting the vacuum source to the booster cylinder at the other side of the piston, means connecting the vacuum source to the last named vacuum chamber and including a valve mechanism, a valve mechanism for opening and closing the last named vacuum chamber to-the atmosphere, a lever connecting the valve mechanisms and pivoted on the diaphragm, and, a yieldable connection between the diaphragm and the rod.

5. In combination with brakes of a" motor vehicle including a brake rigging and a vacuum booster cylinder having a piston connected to the rigging and a vacuum source and a brake'pedal for applying the brakes, a rod connected to said pedal, a housing slidably receiving the rod, meansconnecting said housing to the brake rigging, a diaphragmin said housingand forming vacuum chambers therein .and slidable on said rod, means including a manually actuated control and vent valve connected to one of said chambers and to the-vacuum source, means connecting the other vacuum chamber to the booster cylinder at one side of the piston, means connecting the vacuum source to the booster cylinder at the other side of the piston, means connecting the vacuum source to the last-named vacuum chamber and including a valve mechanism, a valve mechanism for opening and closing the last named vacuum chamber to the atmosphere, a lever connecting the valve mechanisms and pivoted on the diaphragm, a spring seat secured on the rod, and a coil spring bearing against the diaphragm and chambers therein and slidable on said rod, means 1 including a manually actuated control and a vent valve connected to one of said chambers andto the vacuum source, means connecting the other vacuum chamber to the booster cylinderat one. side of thepiston, means connecting the vacuum source to the booster cylinder at the other side i for opening and closing the last named vacuum chamber to the atmosphere,- a lever connecting phragm, a spring seat secured 'on the rod, and a .coil spring bearing against the diaphragm and the spring seat to provide a yieldable connection the valve mechanisms and pivoted on the diabetween the rod and the diaphragm, a second spring seat secured on the rod, and a coil spring interposed between the second seat and the housing, said second seat being capable oi. engaging the housing and thereby connecting the brake -rod to said housing for the application of the 

